Of the 200 pigs the team tested, 70 percent carried a strain of MRSA, ST398, a strain that is known to affect humans.
The scientists found that almost half of 20 workers on local pig farms carried the same strain of MRSA, suggesting a route to the wider community. So far no one has tested MRSA patients in US hospitals to identify whether they carry the same strain.
The federal government is testing meat, but not livestock, for MRSA. In the United Kingdom, at least three people are known to have contracted the ST398 strain, and experts are speculating that contraction is by handling or eating meat.